Tiny right-to-left control flow utility (experiment) utilizing context binding. Allows both sync and async steps. Syntax for context-binding simplified by the experimental strawman operator (https://github.com/zenparsing/es-function-bind). No error/misuse handling. *Uses ES7 features*

example.es7.js

// Syntax 1:
s.val(13)::third::second::first::s.run();

// Syntax 2: (-> s.val completely unnecessary)
third::second::first::s.run(13);

//

// Example programmatic creation of a chain
let chain = third;
chain = chain::second;
chain = chain::first;
chain::s.run(13);

//

function first() {
  this::s.async(function run(i) {
    console.log("first", this, i);
    
    return new Promise((resolve, reject) => {
      setTimeout(() => resolve(this + 2), 100);
    });
  });
}

function second() {
  this::s.chain(function run(i) {
    console.log("second", this, i);
    return this + 3;
  });
}

function third() {
  this::s.chain(function run(i) {
    console.log("third", this, i);
    return this;
  });
}

side-chain.es7.js

const s = (() => {
  let object, i = 0;
  return {
    // initialize the value that is passed as `obj` to each callback passed to `chain`
    val(obj) {
      object = obj;
      i = 0;
    },
    // run code (in `cb` function) safely in the flow 
    chain(cb) {
      object = object::cb(i++);
      if (typeof this === "function") this();
    },
    // async chain
    async async(cb) {
      object = await object::cb(i++);
      if (typeof this === "function") this();
    },
    // initiate flow; can be passed initial value
    run(obj) {
      if (obj) {
        object = obj;
        i = 0;
      }
      this();
    }
  };
})();